SteelSeries has announced PrismCaps which will allow you to upgrade your SteelSeries keyboard (as well as many other brands) by letting the light shine through thanks to their pudding keycaps.
The sets come in either white or black and include a full sets of keys, a keycap puller and two alternate sets of bottom row keycaps just to ensure that it fits a wide variety of keyboards.
They’re currently available on SteelSeries.com (they’ll hit local retail in the next few months) and will set you back about $75 AUD including shipping (use code: DINOSAUR). They should be quite a bit cheaper once they launch locally.
The keycaps are compatible with the: Apex Pro / Apex Pro TKL, Apex 7 / Apex 7 TKL, Apex 5, Apex M750 / Apex M750 TKL/Most MX stems mechanical keyboards even with “non-standard” bottom row.